364 BATHYMETRICAL SURVEY OF 



deep water is all towards the upper end, the lower half of the loch 

 being very shallow. The area enclosed by the 50-feet contour is about 

 half the total length of the loch, and in this part the sections are 

 somewhat U-shaped. A slight shoaling is observable opposite the 

 entrance of the stream near the middle of the eastern shore, where, 

 in the centre, the deepest sounding was 52 feet, with depths of 60 feet 

 and over both to the north-east and south-west. 



Temperature Observations. Serial temperatures in the deepest part 

 indicated practically the same range (5) as in the west loch, and the 

 distribution of temperature was exactly similar, but all parts of the 

 loch were about 1 higher : 



Surface 51'0 Fahr. 



10 feet 47'5 



20 46-2 



50 46-0 



Loch Laggan (see Plate LXXXV.). Loch Laggan is situated in the 

 southern portion of Inverness-shire, between the Highland and West 

 Highland railways, being about equally distant from the nearest points 

 of each. Dalwhinnie, on the Highland railway, is about 6J miles from 

 the upper end of the loch ; Tulloch, on the West Highland railway, is 

 about 6 miles from the lower end. The coach road from Kingussie to 

 Tulloch passes along the northern shore. The loch runs nearly north- 

 east and south-west, and occupies a valley lying between the very high 

 mountains of Badenoch on the south-east and an equally high and more 

 extensive mountain mass of the district of Lochaber on the west. The 

 loch is of the usual elongate narrow form of Scottish lochs, narrowest 

 in the central parts, and somewhat expanded towards each end, where 

 deeper water occurs. The outline is very irregular, and the bottom, as 

 shown by the contours, correspondingly irregular. A number of larger 

 and smaller islands are found in the narrower parts of the loch. The 

 length is a little over 7 miles, the greatest breadth two-thirds of a mile, 

 the mean breadth nearly half a mile, the superficial area about 1900 

 acres, or nearly 3 square miles. The maximum depth is 174 feet, the 

 mean depth 68 feet, and the volume of water about 5600 millions of 

 cubic feet. The loch was surveyed on June 2 and 3, 1902, when the 

 elevation of the lake-surface above the sea was found, by levelling from 

 bench-marks to be 818-6 feet ; the officers of the Ordnance Survey found 

 the elevation to be 818-9 feet above sea-level on October 19, 1867. The 

 shores are wooded nearly throughout, and the scenery wild and pic- 

 turesque (see Fig. 54), the mountains rising abruptly on the north side 

 into a series of peaks, culminating in Creag Meaghaidh, 3700 feet 

 high. On the south-east the high mountains are more distant, Beinn 

 a' Chlachair, over 3500 feet, being 4 miles from the lower end of the 

 loch. Close to the loch on this side, two hills, rather more than 2000 



